Multicentric reticulohistiocytosis successfully treated with infliximab: an illustrative case and evaluation of cytokine expression supporting anti-tumor necrosis factor therapy.

BACKGROUND: Multicentric reticulohistiocytosis (MR) is a rare multisystem granulomatous disease that frequently results in disfiguring cutaneous deposition, destructive arthritis, and debilitating constitutional symptoms. No consistently effective treatment has been identified. Recently, studies characterizing the cytokine expression profile in MR have prompted therapeutic attempts with tumor necrosis factor (TNF) inhibition. Owing to the rarity of the condition, few such cases have been reported, and controlled studies are unlikely to be performed. OBSERVATIONS: A 63-year-old man developed MR refractory to traditional therapies and etanercept therapy. The addition of infliximab to his current regimen of methotrexate sodium and prednisone resulted in a rapid and sustained improvement in his cutaneous, articular, and constitutional manifestations of disease throughout 12 months of follow-up.
CONCLUSIONS: We present this case to highlight the growing body of evidence characterizing the cytokine involvement in MR that has led to successful therapy via TNF inhibition. Our patient responded dramatically to infliximab in combination with methotrexate and prednisone despite previously failing to benefit from etanercept therapy. An analysis of our case combined with those previously reported in the literature suggests that despite some disparity in the response of cutaneous and articular manifestations of MR, TNF blockade is emerging as a promising therapeutic option.